Longmont Events in September

Events in September in Longmont

Here’s your guide to all the happening concerts, festivals and events in September 2026 in Longmont. Catch the best of everything that your city has to offer here. Right from the flea market events to all the festivals; the September 2026 events in Longmont is all curated and sorted for you. Get going, buy your tickets and register to all the fun and exciting events already!

Events in September in Longmont

Fri, 04 Sep, 2026 - 12:00 PM

FREE Longmont Home Show, September 2026

Boulder County Fairgrounds Campground

Newly Added

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Free
Fri, 18 Sep, 2026 - 12:00 PM

Boulder County Ski & Outdoor Expo, September 2026

Boulder County Fairgrounds
Sun, 20 Sep, 2026 - 08:15 AM

Oktoberfest Sprint Triathlon

Union Reservoir

28+ Interested

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FAQs

What are the top free Events in September happening in Longmont?

Here are the top free Events in September in Longmont:

FREE Longmont Home Show, September 2026 is happening on Fri 04 Sep 2026 from 12:00 PM onwards at Boulder County Fairgrounds Campground, Longmont

What are the top Events in September happening in Longmont?

Here are the top Events in September in Longmont:

FREE Longmont Home Show, September 2026 is happening on Fri 04 Sep 2026 from 12:00 PM onwards at Boulder County Fairgrounds Campground, Longmont
Boulder County Ski & Outdoor Expo, September 2026 is happening on Fri 18 Sep 2026 from 12:00 PM onwards at Boulder County Fairgrounds, Longmont
Oktoberfest Sprint Triathlon is happening on Sun 20 Sep 2026 from 8:15 AM onwards at Union Reservoir, Longmont